中文摘要：

一个（t，n）门限方案就是将密钥K分给n个成员，而任意t个成员合作可以生成密钥K，但只有t-1个成员或者更少的成员不能生成该密钥．大多数（t，n）门限方案都基于Lagrange插值多项式或者是同余理论．文章提出了一种新的基于线性多项式的有向门限方案．此方案中，对消息的签名和验证必须在接受方参与下才能进行．

英文摘要：

A （t,n） threshold scheme is a scheme to distribute a secret key K to n users in such a way that any t users can cooperate to reconstruct K but a collusion of t - 1 or less users reveal nothing about the secret. Most （t, n） threshold schemes are based on Lagrange interpolation or Chinese Remainder Theorem. This paper proposes a new （t, n） directed-threshold signature scheme based on multivariate linear polynomial and Schnorr＇s signature scheme. In this signature scheme, the signature receiver has full control over the signature verification process. Nobody can check the validity of signature without the cooperation of the receiver.